346 STATE HORTICULTURAL SOCIETY. 



THE PEACH YELLOWS. 



The yellows of the peach is spreading in western New York, and it is 

 becoming a very serious menace to peach culture. Investigations into the 

 nature of this disease have been carried on for the last three or four years 

 by the department of agriculture at Washington. Little has been said 

 concerning these investigations, and people are not aware of the extent to 

 which they have been carried. In order to learn something of their scope, 

 I visited the Chesapeake peninsula in October and examined the field 

 experiments under progress. Dr. E. F. Smith is the special agent of the 

 department of agriculture, who is investigating the disease. In this region 

 he has eighty acres of orchard under direct experiment, forty of which, 

 scattered through twelve orchards in Delaware and Maryland, are devoted 

 to fertilizer tests. These fertilizer tests are above a hundred in number, 

 and comprise treatment with nitrogen, potash, and phosphorus, and many 

 combinations of them. He has tried all of the fertilizer remedies which 

 have been recommended for the cure of the disease and for its prevention. 

 These have been tried upon all kinds of soils, and upon trees of all ages. 

 They have been used with exceeding care, and they comprise the largest 

 field experiments of this nature, upon diseases of plants, yet made in this 

 country. It is evident upon examining these orchards that there is no 

 fertilizer nor combination of fertilizers which will either cure or prevent 

 yellows Many of the fertilizers, especially those rich in nitrogen, 

 have a wonderful effect upon the vigor of the tree, but they do not prevent 

 yellows, nor cure it. All the investigations so far made, go to show that 

 yellows is a specific disease, entirely independent of soil or surroundings. 



Many investigations in other directions have been made, and many 

 important facts have been obtained concerning the nature of the disease, 

 but so far its cause has not been determined. The disease is an exceedingly 

 obscure one, much more so than pear blight or any other disease with 

 which we are familiar. 



The New Jersey, Delaware and Maryland orchards are being rapidly 

 decimated with yellows; in fact, the upper portion of Delaware is prac- 

 tically devastated of peach trees, and the upper part of the Chesapeake 

 peninsula in Maryland is no longer a profitable peach region. There are 

 acres upon acres of orchard in which more than every other tree is visably 

 diseased, and in large areas it is almost impossible to find a single healthy 

 tree. There has been very little united attempt toward controlling 

 yellows in these regions, and for that reason this present destruction 

 threatens the industry. It is useful to compare the resrdts in this region 

 with those of the Michigan peach region, where a definite law was early 

 enacted and which has been enforced vigorously. In Michigan yellows is 

 on the decrease and the planting of orchards is on the increase. In Mary- 

 land and Delaware, yellows is rapidly on the increase and orcharding is 

 mostly on the decrease. The only remedy so far known is eradication of 

 the tree as soon as the disease is seen. The disease is constitutional, and 

 even when we have found the cause it will probably remain incurable. 

 Yet there is no reason for undue alarm in the matter, because the experi- 



